I have discovered that the sysinfo plugin written by Kikko forces VDR-1.5.x to use the default font rather then the user-defined setting. I emailed the author and he responded by saying he won't fix his plugin until Klaus releases a final version of 1.5, which could be quite a long time. I don't understand the logic behind his decision but nonetheless it's his to make so ...
I don't think the problem is that hard to fix but I don't have enough knowledge of C to do it myself so I'm asking publically if anyone can have a look and come up with a possible fix/patch for the problem. The newest version of sysinfo is 0.1.0a, which is what I'm using. The plugin can be found at: http://kikko77.altervista.org/index.php?mod=Download
Any help with this is greatly appreciated.